JP7265196B2 - light emitting device - Google Patents

Description

The present invention relates to light emitting devices.

Light-emitting devices using light-emitting elements such as light-emitting diodes (LEDs) are used for illumination and the like. Some of such light emitting devices use a large number of LED chips to increase the amount of light.

However, if the light emitted by many LED chips is output as it is, the outer shape of each LED chip may be visually recognized due to the strong directivity of the LED light. For example, in the case of a light-emitting element in which square LED chips are arranged in a grid pattern, a grid pattern may appear as the output light of the LED.

Therefore, it is conceivable to provide a diffusing optical system for diffusing and emitting the light emitted from the LED chip. For example, as shown in FIG. 11, the light-emitting device 110 may be provided with a diffusion optical system composed of a cylindrical light guide pipe 111 and a diffusion glass 130 adhered to the light guide pipe 111 .

However, when a large number of LED chips are arranged intensively, it is conceivable that the amount of heat generated increases. For example, in the configuration of FIG. 11 , if the light guide pipe 111 is made of resin, a difference in coefficient of linear expansion will occur between the diffusion glass 130 and the light guide pipe 111 . That is, when the temperature is high, the amount of deformation of the resin-made light guide pipe 111 increases, while the diffusion glass 130 hardly expands. As a result of being pushed back against the diffusion glass 130 by the reaction, the resin-made light guide pipe 111 may be damaged. Thus, when the diffusing optical system is integrally molded, there is a problem that damage due to thermal stress occurs.

Japanese Patent Application Laid-Open No. 2001-108878 Japanese Utility Model Laid-Open No. 03-092614 JP-A-10-319873 JP 2006-178382 A

The present invention has been made in view of such a background, and one of its objects is to provide a light-emitting device in which damage due to thermal stress is reduced.

According to a light-emitting device according to an aspect of the present invention, a plurality of light-emitting elements; a cylindrical pipe portion arranged on the substrate so as to surround the arrangement area; a light diffusion portion made of a material different from that of the pipe portion and diffusing and transmitting the light emitted from the plurality of light emitting elements; and a cover portion that holds the light diffusing portion between itself and the pipe portion, the light diffusing portion being arranged on the upper surface of the pipe portion, and the cover portion being attached to the pipe portion. a covering area that covers the outer surface of the pipe portion and has an inner diameter larger than the outer diameter; and a holding area covering the upper end of the light diffusing section, wherein the height difference between the arrangement position of the light diffusing section on the upper surface of the pipe section and the lower surface of the holding area is larger than the thickness of the light diffusing section. A margin in the thickness direction is formed between the holding region and the light diffusing portion.

According to the above aspect, it is possible to obtain a light-emitting device in which damage due to thermal stress is reduced.

1 is a side view of a lighting device according to Embodiment 1. FIG. FIG. 2 is an exploded perspective view of the illumination device of FIG. 1 with a reflector removed; 3 is an enlarged perspective view of the light emitting device of FIG. 2; FIG. 4 is an exploded perspective view of the light emitting device of FIG. 3; FIG. FIG. 5 is an exploded perspective view of the light emitting device of FIG. 4 as seen obliquely from below; 4 is a cross-sectional view taken along line VI-VI of FIG. 3; FIG. FIG. 7 is an enlarged sectional view of a main portion of FIG. 6; FIG. 8A is a plan view showing an example of an arrangement pattern of light emitting elements, and FIG. 8B is a plan view showing another example. It is a perspective view which shows the cover part which concerns on a modification. 10A and 10B are enlarged cross-sectional views showing an example of the inner surface of the holding area. 1 is a perspective view showing a light-emitting device provided with a diffusing optical system that the present inventors experimentally produced; FIG.

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments and examples according to the present invention will be described based on the drawings. However, the embodiments and examples shown below are examples for embodying the technical idea of the present invention, and the present invention is not limited to the following. Also, the sizes and positional relationships of members shown in each drawing may be exaggerated for clarity of explanation. Furthermore, in the following description, the same names and symbols indicate the same or homogeneous members, and detailed description thereof will be omitted as appropriate. Furthermore, each element constituting the embodiments and examples according to the present invention may be configured by forming a plurality of elements with the same member, and one member may be used as a plurality of elements, or conversely, one member function can be shared by a plurality of members. Also, the contents described in some of the examples and embodiments can also be used in other examples and embodiments.
(Lighting device)

1 to 7 show a lighting device 1000 according to Embodiment 1. FIG. Here, as an example of the light emitting device, an example applied to a medical lighting device is shown. In these figures, FIG. 1 is a side view of the lighting device 1000 according to Embodiment 1, FIG. 2 is an exploded perspective view of the lighting device 1000 of FIG. 1 with the reflector 50 removed, and FIG. 4 is an exploded perspective view of the light emitting device 100 of FIG. 3, FIG. 5 is an exploded perspective view of the light emitting device 100 of FIG. , and FIG. 7 are enlarged sectional views of essential parts of FIG. 6, respectively. The lighting device 1000 shown in FIGS. 1 and 2 has a reflector 50 in the light emitting device 100 . The reflector 50 is fixed to a light-emitting surface that emits light emitted from the light-emitting device 100, and reflects the light entering the interior of the reflector 50 from the light-emitting device 100 on the reflecting surface. The reflector 50 constitutes a collimating optical system that makes the light from the light emitting device 100 closer to parallel light. Also, instead of the reflector 50, a lens may be used as the optical system. In addition, a reflective surface having excellent reflective efficiency is formed on the end face. The reflective surface is preferably made of metal. Note that the reflector does not necessarily have to be a separate member, and may be configured integrally with the light emitting device. Also, the reflector is not essential and can be omitted.
(Light emitting device 100)

The light emitting device 100 shown in FIGS. 3, 4, and 5 includes a plurality of light emitting elements 1, a substrate 10 on which the plurality of light emitting elements 1 are mounted, and a cylinder arranged on the substrate 10 so as to surround the light emitting elements 1. a shaped pipe portion 20 , a light diffusion portion 30 fixed to the upper surface of the pipe portion 20 , and a cover portion 40 fixed to the substrate 10 with the light diffusion portion 30 sandwiched between the pipe portion 20 and the cover portion 40 .
(Light emitting element 1)

A light-emitting diode is normally used as the light-emitting element 1 . The light-emitting element 1 can be appropriately selected according to the purpose, such as its composition, emission color or wavelength, size, number, and the like. For example, as blue and green light emitting elements, semiconductor layers such as ZnSe, nitride semiconductors ( _{InXAlYGa1 -XYN ,} 0≤X, 0≤Y, X+Y≤1), GaP, etc. are used. Examples of red light emitting elements include those using semiconductor layers such as GaAlAs and AlInGaP.

The light-emitting device 1 is generally formed by stacking semiconductor layers on a growth substrate (for example, a sapphire substrate). The growth substrate may have unevenness on the bonding surface with the semiconductor layer. This makes it possible to intentionally change the critical angle at which the light emitted from the semiconductor layer impinges on the growth substrate so that the light can be easily extracted to the outside of the growth substrate. The growth substrate may be removed after stacking the semiconductor layers. The growth substrate can be removed by, for example, polishing, LLO (Laser Lift Off), or the like.

The light emitting element 1 may have a pair of positive and negative electrodes on the same surface side. As a result, the light-emitting element 1 can be flip-chip mounted to the conductive pattern previously formed in the arrangement area on the substrate 10 . In this case, the surface opposite to the surface on which the pair of electrodes is formed serves as the light extraction surface. In flip-chip mounting, the light-emitting element 1 and the conductive pattern of the substrate 10 are electrically connected by using a metal bump such as Au or Cu, a paste-like bonding member having conductivity such as solder, a thin-film bonding member, or the like. Connected. Alternatively, in the case of face-up mounting, the surface on which the pair of electrodes are formed may be used as the light extraction surface. Alternatively, the light emitting element may have a pair of positive and negative electrodes on different sides. In this case, one electrode is adhered to the substrate 10 with a conductive adhesive, and the other electrode is connected to the substrate 10 with a conductive wire or the like.

Further, the light-emitting element may be combined with a phosphor that absorbs the light emitted from the light-emitting element 1 and converts it into light of a different wavelength. As the phosphor, one known in the art can be used. For example, cerium-activated yttrium-aluminum-garnet-based phosphor (YAG:Ce), cerium-activated lutetium-aluminum-garnet-based phosphor (LAG:Ce), europium and/or chromium-activated nitrogen containing calcium aluminosilicate phosphor (CaO—Al ₂ O ₃ —SiO ₂ :Eu,Cr), europium-activated silicate phosphor ((Sr,Ba) ₂ SiO ₄ :Eu), β-sialon phosphor, Nitride phosphors such as chlorosilicate phosphors, CASN or SCASN phosphors, rare earth metal nitride phosphors, oxynitride phosphors, KSF phosphors (K ₂ SiF ₆ :Mn), sulfide phosphors and quantum dot phosphors. By combining these phosphors with a blue light emitting element or an ultraviolet light emitting element, light emitting devices of various colors (for example, white light emitting devices) can be obtained. When a light-emitting device capable of emitting white light using a blue light-emitting element is used, the type and concentration of the phosphor coating the light-emitting element are adjusted to provide white light.

A plurality of light-emitting elements 1 are included in one light-emitting device 100 . The plurality of light emitting elements 1 are arranged in line. For example, they may be arranged in one row or in multiple rows. The number of light-emitting elements 1 can be appropriately set according to the characteristics, size, etc. of the light-emitting device to be obtained.

It is preferable that the plurality of aligned light emitting elements 1 are close to each other, and considering the luminance distribution and the like, the distance between the light emitting elements is about 5 to 50% of the length of the maximum side of the light emitting elements 1. about 5 to 30% is preferable, and about 5 to 20% is more preferable. By arranging the light emitting elements close to each other in this manner, a uniform and excellent luminance distribution can be ensured. As a result, the light emitting device 10 can be a surface light source with less light emission unevenness and high light emission quality.

Further, a plurality of light emitting elements 1 may be configured by combining different emission colors. For example, a first light emitting element 1a that emits a first luminescent color and a second light emitting element 1b that emits a different luminescent color from the first light emitting element are included. Specifically, an incandescent light emitting diode and a white light emitting diode can be combined.

Furthermore, in examples such as FIG. 4, a plurality of light emitting elements 1 are arranged in a circular shape. At this time, various patterns can be adopted as the arrangement pattern when arranging the plurality of different types of light emitting elements 1 . For example, as shown in FIG. 8A, light emitting elements 1 of the same type, for example, first light emitting elements 1a and second light emitting elements 1b are linearly arranged and alternately arranged. Alternatively, as shown in FIG. 8B, light emitting elements of the same kind may be arranged not in a straight line but in a wavy shape. In the example of FIG. 8B, a gentle V-shaped pattern with its center depressed in the horizontal direction is alternately arranged for each line. By alternately arranging such non-linear curves for each light emitting element of the same type, the color mixing property is improved compared to the pattern of alternately arranging the light emitting elements of the same type arranged linearly as shown in FIG. 8A. can be increased.
(Substrate 10)

The substrate 10 is a mounting substrate on which a plurality of light emitting elements 1 are arranged in a predetermined pattern and mounted thereon. The substrate 10 usually consists of a conductive pattern and a base supporting it. Examples of the material of the substrate include a substrate made of an insulating material such as glass epoxy, resin, or ceramics, or a metal member such as aluminum on which an insulating material is formed. Among them, those using ceramics with high heat resistance and weather resistance are preferable. Ceramics include alumina, aluminum nitride, mullite, and the like. These ceramics may be combined with an insulating material such as BT resin, glass epoxy, or epoxy resin. The thickness of the substrate is, for example, about 100 μm to 1 mm. On this substrate 10, an arrangement area is formed in which a plurality of light emitting elements 1 are arranged.
(Pipe portion 20)

The pipe portion 20 is fixed on the substrate 10 so as to surround the arrangement area. Also, the inner surface of the pipe portion 20 is made of a member with enhanced light reflectivity. For example, it can be made of white resin, metal-plated resin, or a metal tube. When the pipe portion 20 is made of resin, polycarbonate, polystyrene, acrylonitrile-butadiene-styrene resin (ABS resin), polyvinyl chloride resin, polyethylene terephthalate, polybutylene terephthalate, polypropylene, or the like can be used. Polybutylene terephthalate is particularly preferred in terms of strength. In this manner, by enclosing the plurality of light emitting elements 1 in a cylindrical shape, the pipe portion 20 can be used as a light guide for guiding light. Specifically, the shape of the pipe portion 20 is a cylinder with both ends opened. One opening is used as an introduction end for introducing light, and the other opening is used as an emission end for emitting light. Furthermore, the introduction end is arranged on the substrate 10 side, and the light diffusion section 30 is arranged on the emission end. In this way, by separating the light diffusion plate from the light emitting element 1, which is the light source, with the pipe portion 20, the light path length can be ensured and the light diffusion effect can be enhanced.

The end surface of the tubular pipe portion 20 is annular. However, the end face of the cylindrical shape is not limited to the annular configuration, and may be elliptical, rectangular, polygonal, or the like. This pipe section 20 also has a first pipe region 21 and a second pipe region 22 . The first pipe region 21 has a first inner diameter D<b>1 that is smaller than the outer diameter of the light diffusing portion 30 . The second pipe region 22 has a second inner diameter D2 above the first pipe region 21 that is greater than the first inner diameter D1. Also, the height H2 of the second pipe region 22 is formed higher than the thickness H3 of the light diffusion portion 30, which will be described later. The difference between the thickness H3 of the light diffusion portion 30 and the height H2 of the second pipe region 22 is the thickness direction margin MV, which will be described later.

On the other hand, the first pipe region 21 has a recessed portion 23 higher than the thickness of the light emitting element 1 at the lower end of its inner wall. In the example shown in the exploded perspective view of FIG. 5 and the cross-sectional view of FIG. 6, the recessed portion 23 is formed by chamfering the edge of the light guide end of the pipe portion 20 or scraping it off stepwise. By forming such recessed portion 23 , when pipe portion 20 is fixed on substrate 10 during assembly of light emitting device 100 , it is possible to reduce the risk of the inner wall of pipe portion 20 coming into contact with light emitting device 100 . will be protected.

The height HP of the pipe portion 20 is preferably formed smaller than the inner diameter of the pipe, specifically the second inner diameter D2. As a result, although the light diffusion plate is separated from the plurality of light emitting elements 1 by the pipe portion 20 to secure the optical path length, the optical path length becomes longer and the light is reflected and absorbed in the pipe portion 20, resulting in a decrease in efficiency. It is possible to suppress the situation where
(Pipe-side base region 24)

The pipe portion 20 also has a pipe-side base region 24 for fixing to the substrate 10 that extends outward from the lower end of the first pipe region 21 . A plurality of pipe-side base regions 24 are preferably provided. A plurality of pipe-side base regions 24 are arranged at regular intervals around the pipe portion 20 . In the example of FIGS. 4 and 5, three pipe-side base regions 24 are arranged at intervals of approximately 120° in plan view. Further, on the back side of each pipe-side base region 24, that is, on the surface in contact with the substrate 10, as shown in FIG. Further, on the substrate 10 side, a substrate side first pin hole 15 is opened as a substrate side first fixing portion at a position corresponding to the pipe side pin 25 when the pipe portion 20 is arranged in a posture surrounding the arrangement area. . The pipe portion 20 is fixed on the substrate 10 by fitting the pipe-side pin 25 into the substrate-side first pin hole 15 . In the present invention, the structure for fixing the pipe portion to the substrate is not limited to fitting of pins and pin holes, and other known fixing methods such as screwing with screws or bolts, crimping, bonding, etc. can be used as appropriate.
(Light diffusion part 30)

The light diffusion part 30 is a member for diffusing and transmitting the light emitted from the plurality of light emitting elements 1 . Such a light diffusing part 30 has translucency, and has rough surfaces on both sides or one side, or diffuses a diffusing material for diffusing light. Also, the light diffusing portion 30 is made of a material different from that of the pipe portion 20 . For example, the deterioration can be suppressed by configuring the light diffusing section 30 with a glass plate having excellent heat resistance and light resistance. In particular, if a light-emitting element that emits strong light such as an LED is used, it will be exposed to strong light. If multiple LEDs are used, the light will be even stronger. In addition, the amount of heat generated by a plurality of light emitting elements also increases accordingly. For this reason, the light diffusing portion 30 is required to have high durability such as light resistance and heat resistance, and an inorganic material is preferable to an organic resin material.

The light diffusion part 30 is arranged inside the second pipe region 22 and at the upper end of the first pipe region 21 . Thus, by providing the pipe portion 20 as a light guide tube and providing the light diffusion portion 30 at the emission end, the light emitted from the plurality of light emitting elements 1 can be mixed relatively uniformly, and high quality light with little unevenness can be obtained. It becomes possible to obtain a light-emitting device.

Examples of materials forming the light diffusing portion 30 include glass materials such as silicate glass, borosilicate glass, and quartz glass. Sandblasting, polishing, or the like can be used as a method of roughening both or one side of the light diffusing portion 30 .

In addition, the light diffusing section 30 may have a phosphor or the like in addition to the diffusing material. The diffusing material and the phosphor may be contained inside the light diffusing section 30 , or a layer containing the diffusing material and the phosphor may be provided on both or one side of the light diffusing section 30 . As a method for forming the layer containing the diffusing material and the phosphor, for example, printing, spraying, electrodeposition, and electrostatic coating can be used. Alternatively, a phosphor sheet or the like made of resin containing phosphor may be adhered to the light diffusing portion.

As the diffusing material, for example, silica, titanium oxide, zirconium oxide, aluminum oxide, or the like can be used.
(Cover part 40)

The cover portion 40 is a member for holding the light diffusion portion 30 between itself and the pipe portion 20 . This cover part 40 is fixed to the substrate 10 . The cover portion 40 includes a covering area 41 , a holding area 42 and a cover-side base area 43 . The cover portion 40 is made of polycarbonate, polystyrene, acrylonitrile-butadiene-styrene resin (ABS resin), polyvinyl chloride resin, polyethylene terephthalate, polybutylene terephthalate, polypropylene, or the like. Preferably, it is made of the same member as the pipe portion 20 .
(Covered region 41)

A covered region 41 of the cover portion 40 is formed in a tubular shape having an inner diameter larger than the outer diameter of the pipe portion 20 . The covering region 41 is formed according to the shape of the pipe portion 20, and when the pipe portion 20 is formed in a cylindrical shape, the covering region 41 is formed in a cylindrical shape that is one size larger than this. The outer surface of the pipe portion 20 is covered with this covering region 41 .
(Holding area 42)

The retaining region 42 extends inwardly from the upper end of the covering region 41 to form an open window with an inner diameter DC less than the second inner diameter D2. By forming in this way, as shown in the cross-sectional view of FIG. 6, the holding area 42 covers the upper end of the second pipe area 22 and holds the periphery of the light diffusion part 30 therebetween.
(Deformation mitigation function due to thermal expansion)

The light diffusing portion 30 is not directly fixed to the pipe portion 20 , but is placed and held on a step of the pipe portion 20 . In other words, the light diffusion portion 30 is held by the pipe portion 20 and the cover portion 40, and the pipe portion 20 and the cover portion 40 are fixed to the substrate 10, respectively. That is, the pipe portion 20 and the cover portion 40 are also not directly fixed to each other. Such a configuration can relieve stress caused by thermal expansion.

When the pipe portion that constitutes the light guide tube is made of an organic material such as resin, the coefficient of linear expansion is different from that of the light diffusion portion that is made of an inorganic material such as glass. is larger than the light diffusion part of Therefore, when the light diffusing portion is molded integrally with the pipe portion, when the pipe portion expands due to heat at the joint interface between the pipe portion and the light diffusing portion and presses the light diffusing portion, the pipe portion is damaged by the reaction. It was possible. On the other hand, in the light-emitting device 100 according to the first embodiment, the pipe portion 20 and the light diffusion portion 30 are not formed integrally, but are held in a state in which a gap (margin) is intentionally provided, so to speak, for play. By arranging it in a specific manner, such damage due to thermal stress is avoided.
(margin)

As described above, a margin is provided between the light diffusion section 30 and the pipe section 20 or cover section 40 that holds it. Specifically, between the light diffusion section 30 and the second pipe region 22, that is, the horizontal margin MH of the light diffusion section 30, and between the light diffusion section 30 and the holding region 42, that is, the light diffusion A thickness direction margin MV, which is the vertical direction of the portion 30, is formed respectively. By providing such a margin, when the pipe portion 20 and the cover portion 40, which have a larger coefficient of linear expansion than the light diffusing portion 30, expand due to the heat generated by the light emitting element, they are pressed by the contact surface with the light diffusing portion 30. It is possible to absorb the situation in which cracks, distortions, etc., occur due to deformation by the margin.

Moreover, it is preferable to form the lateral margin MH larger than the thickness margin MV. Accordingly, by setting a larger margin in the circumferential direction than in the thickness direction, where the amount of deformation due to thermal expansion increases, it is possible to suppress deformation in the circumferential direction and more reliably protect the light emitting device 100 . .

In this way, by separating the light diffusion plate from the plurality of light emitting elements 1 by means of the pipe portion 20, in addition to securing the optical path length and enhancing the light diffusion effect, the coefficient of linear expansion is higher than that of the light diffusion portion 30. When the pipe portion 20 and the outer portion, which have a large diameter, expand due to the heat generated by the light emitting element 1, they are pressed by the contact surface with the light diffusing portion 30 and deformed, causing cracks and distortions. It becomes possible to
(Cover-side base region 43)

The cover-side base region 43 is a member for fixing the cover portion 40 to the substrate 10 . The cover-side base region 43 extends outward from the lower end of the cover region 41 . In examples such as FIG. 4, the cover-side base region 43 is formed in a triangular shape. A covering region 41 is provided in the center of the triangular base region. In other words, the cylindrical covered region 41 in plan view is provided in a posture substantially inscribed in the triangular cover-side base region 43 . At each vertex of the triangle forming the cover-side base region 43, a cover-side through-hole 44 is formed as a cover-side fixing portion for fixing to the substrate 10. As shown in FIG. On the substrate 10 side, a substrate-side second through hole 16 is formed as a substrate-side second fixing portion at a position corresponding to the cover-side through hole 44 when the cover portion 40 is arranged. A pin material PN such as a screw, a bolt, or a rivet pin is inserted into the cover side through hole 44 and the board side second through hole 16 to fix the cover part 40 to the board 10 . The substrate-side second through hole 16 is preferably formed as an elongated hole. As a result, the cover portion 40 can be reliably fixed to the substrate 10 by absorbing some manufacturing tolerances and positional deviations. 4 and 5, the structure for fixing the cover portion 40 to the substrate 10 is not limited to the combination of the cover-side through-hole 44 and the substrate-side second through-hole 16, and any known fixing structure can be used as appropriate. Needless to say. For example, in the modification shown in FIG. 9, a notch 44B is formed as the cover-side fixing portion instead of the cover-side through hole. The cover-side fixing portion of this configuration can be screwed into the substrate-side second through hole 16 of the substrate 10 with a pin member such as a screw. Further, since this configuration can cope with a slight positional deviation, the board-side second through-hole 16 does not have to be an elongated hole.

On the substrate 10, the substrate-side first fixing position where the pipe portion 20 is fixed and the substrate-side second fixing position where the cover portion 40 is fixed are different positions in the examples of FIGS. That is, the first fixing positions on the board side and the second fixing positions on the board side are provided in the same number, and are provided alternately so that the second fixing positions are positioned between the first fixing positions. Thereby, the pipe portion 20 and the cover portion 40 can be stably and reliably fixed to the substrate 10 .

Moreover, the cover part 40 can form a slit 46 communicating with the covering part between the cover-side fixed parts. In the example of the cover portion 40 shown in FIG. 1 , each corner of the triangular cover-side base region 43 is bent stepwise and brought into contact with the substrate 10 . A slit 46 is formed in the other area away from the substrate 10 . Warping due to heat can be suppressed by the slits 46 . Further, through this slit 46 , the pipe portion 20 covered with the cover portion 40 can partially expose the pipe-side base region 24 from the cover portion 40 . Thereby, the cover part 40 can be fixed to the substrate 10 without completely covering the pipe part 20 . In other words, the light diffusion portion 30 can be held by covering the pipe-side pipe region 21 and the second pipe region 22 of the pipe portion 20 without making the cover portion 40 larger than necessary.

However, in the present invention, the fixing position of the pipe portion and the cover portion may be common. For example, by providing a fixing hole in the pipe-side base region and arranging it so as to overlap with the cover-side through hole, it is possible to obtain the advantage that the pipe portion and the cover portion can be simultaneously fixed to the substrate with a common screw or the like.

The inner surface 47' of the retaining area 42' may be vertical as shown in the enlarged cross-sectional view of Figure 10A, but is preferably tapered as shown in the enlarged cross-sectional view of Figure 10B. In the example shown in FIG. 10B , the inner surface 47 of the holding region 42 of the cover 40, that is, the end surface of the opening window is inclined downward in a cross-sectional view, thereby reducing the light reflected component due to the inclined end surface. can be reduced. This effectively prevents the light from being reflected by the edge of the cover portion 40' covering the light diffusing portion 30 and projecting the projected light pattern in a double annular shape along the edge of the cover portion 40'. can be avoided.

A light-emitting device according to an embodiment of the present invention can be suitably used as a shadowless lamp for medical use.

DESCRIPTION OF SYMBOLS 1000... Lighting apparatus 100... Light-emitting device 1... Light-emitting element; 1a... First light-emitting element; First pipe region 22 Second pipe region 23 Recess 24 Pipe-side base region 25 Pipe-side pin 30 Light diffusion portions 40, 40' Cover portion 41 Coating regions 42, 42' Holding region 43 ... cover-side base region 44 ... cover-side through hole; 44B ... notch 46 ... slit 47, 47' ... inner surface of holding region 50 ... reflector 110 ... light emitting device 111 ... light guide pipe 130 ... diffusion glass D1 ... first inner diameter D2 Second inner diameter DC Internal diameter of holding region H2 Height of second pipe region H3 Thickness of light diffusion portion HP Height of pipe portion MV Margin in thickness direction MH Margin in lateral direction PN Pin material

Claims (10)

a plurality of light emitting elements;
a substrate having an upper surface provided with an arrangement region in which the plurality of light emitting elements are arranged in a predetermined pattern;
a tubular pipe portion fixed to the substrate and arranged on the substrate so as to surround the arrangement area;
a light diffusing portion made of a material different from that of the pipe portion and diffusing and transmitting the light emitted from the plurality of light emitting elements;
a cover portion fixed to the substrate and holding the light diffusion portion between itself and the pipe portion;
with
The light diffusion portion is arranged on the upper surface of the pipe portion,
The cover part has an inner diameter larger than the outer diameter of the pipe part, and has a covering area covering the outer surface of the pipe part. and a holding region that covers the upper end of the light diffusing portion and has an inner diameter smaller than
The difference in height between the arrangement position of the light diffusing portion on the upper surface of the pipe portion and the lower surface of the holding area is formed so as to be larger than the thickness of the light diffusing portion,
A light-emitting device in which a gap is formed as a margin in the thickness direction between the holding area and the light diffusing section. The light emitting device according to claim 1,
The pipe portion
a first pipe region having a first inner diameter smaller than the outer shape of the light diffusing portion and having the light diffusing portion disposed on an upper surface thereof;
a pipe-side base region for fixing to the substrate, extending outwardly from the first pipe region;
A light emitting device comprising: The light emitting device according to claim 2,
The light-emitting device, wherein the cover portion includes a cover-side base region for fixing to the substrate, the cover portion extending outward from the covering region. a plurality of light emitting elements;
a substrate having an upper surface provided with an arrangement region in which the plurality of light emitting elements are arranged in a predetermined pattern;
a tubular pipe portion fixed to the substrate and arranged on the substrate so as to surround the arrangement area;
a light diffusing portion made of a material different from that of the pipe portion and diffusing and transmitting the light emitted from the plurality of light emitting elements;
a cover portion fixed to the substrate and holding the light diffusion portion between itself and the pipe portion;
with
The light diffusion portion is arranged on the upper surface of the pipe portion,
The cover part has an inner diameter larger than the outer diameter of the pipe part, and has a covering area covering the outer surface of the pipe part. and a holding region that covers the upper end of the light diffusing portion and has an inner diameter smaller than
The difference in height between the arrangement position of the light diffusing portion on the upper surface of the pipe portion and the lower surface of the holding area is formed so as to be larger than the thickness of the light diffusing portion,
A thickness direction margin is formed between the holding region and the light diffusion portion,
The pipe portion
a first pipe region having a first inner diameter smaller than the outer shape of the light diffusing portion and having the light diffusing portion disposed on an upper surface thereof;
a pipe-side base region for fixing to the substrate, extending outwardly from the first pipe region;
and
the cover portion includes a cover-side base region for fixing to the substrate, extending outward from the covering region;
The light-emitting device, wherein the pipe-side base region has a pipe-side fixing portion fixed to the substrate. The light emitting device according to claim 4,
The light-emitting device, wherein the cover-side base region has a cover-side fixing portion fixed to the substrate. A light emitting device according to claim 5,
The light emitting device, wherein the pipe-side fixing portion is arranged so as to overlap with the cover-side fixing portion. The light emitting device according to any one of claims 2 to 6,
A light-emitting device in which the first pipe region has a recess formed on the inner wall of the lower end thereof, the recess being higher than the thickness of the light-emitting element. The light emitting device according to any one of claims 1 to 7,
A light-emitting device in which the light diffusing portion is made of a glass plate. A light emitting device according to claim 8,
A light-emitting device in which the pipe portion and the cover portion are made of the same material. The light emitting device according to any one of claims 1 to 9,
The plurality of light emitting elements are
a first light emitting element that emits a first emission color;
A light-emitting device comprising a second light-emitting element emitting light in a color different from that of the first light-emitting element.

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